To make ceramics from powder, we first mix the raw powders and fire them (calcination) to form the target compound, and then shape that powder and consolidate it into a solid below its melting point (sintering). In ① you will see how, during calcination, two kinds of powder in contact mix by atomic diffusion and become an ordered compound or a solid solution. In ② through ⑦ we look at sintering through a two-particle schematic and densification curves. In ② you confirm that the driving force is the decrease of surface energy, and in ③ that the speed of neck growth depends on the mass-transport mechanism, and in ④ you see that whether the sample shrinks depends on whether the source of matter is the particle surface or the grain boundary. In ⑤ and ⑥ you draw densification curves and see that densification stops when grain growth leaves pores behind, and in ⑦ you compare how well techniques that assist sintering work.
Mochizuki Research Group, Tokyo University of Science | The densification curves in ⑤, ⑥ and ⑦ are computed on the spot by numerically integrating equations adapted from Coble’s intermediate-stage model, using educational coefficients; they are meant only for seeing trends. Detailed explanations and references are on the explanation page on the theory of sintering (in Japanese).